1. Faculty of Science, Department of Chemistry, University of Maroua, Maroua, Cameroon
2. Department of Chemistry, Higher Teachers’ Training College Maroua, Maroua, Cameroon
3. Department of Agricultural and Environmental Engineering, College of Technology, University of Bamenda, Bamenda, Cameroon
4. Higher National Polytechnic Maroua, Department of Textile Engineering and Leather, University of Maroua, Maroua, Cameroon